The present invention relates to electric sealers, and more particularly to a hand-held electric sealer with safety means which controls the heating of the sealing mechanism, and stops the sealing mechanism from being triggered by an erroneous action.
A variety of electric sealers have been developed, and have appeared on the market. These conventional electric sealers are designed to be energized by AC power supply, or DC power supply. U.S. Pat. No. 5,142,123 discloses an electric an electric sealer energizable by internal battery set or external AC adapter.
It is one object of the present invention to provide an electric sealer which is hand-held and safe to use. It is another object of the present invention to provide an electric sealer which is energizable by an internal battery set or external AC adapter. It is still another object of the present invention to provide a hand-held electric sealer which includes means to stop the sealing mechanism from being triggered by an erroneous action.
According to one embodiment of the present invention, the hand-held electric sealer comprises a casing, a sealing mechanism, a press bar, and safety means. The sealing a mechanism comprises a heat insulative base, a heating wire, and two metal locating plates. The heat insulative base has a projecting block on the middle. The heating wire is mounted on the projecting block of the heat insulative base. The metal locating plates are fastened to the heat insulative base at two opposite sides to hold down the heating wire. A heat resistive cover sheet may be fastened to the projecting block of the heat insulative base, and covered on the heating wire. The number of the heating wire may be increased if desired. The heat insulative base of the sealing mechanism can be made of ceramics, bakelite, heat insulative plastics., or any material that resists heat as high as about 200xc2x0 C. The press bar has one end, namely the fixed end, pivotably connected to the casing, and an opposite end, namely the free end, mounted with a heat insulative block. When the press bar is pressed down, the heat insulative block is lowered with the free end of the press bar and forced against the heat insulative base of the sealing mechanism to clamp the mouth of the plastic bag, enabling the mouth of the plastic bag to sealed. The safety means-controls the heating of the heating wire of the sealing mechanism, and stops the sealing mechanism from being triggered by an accident . The safety means can be a stop plate pivotably to the outside wall of the casing, and turned between a first position where the stop plate is suspended above the sealing mechanism to stop the heat insulative block of the press bar from contacting the projecting block of the heat insulative base of the sealing mechanism, and a second position where the stop plate is moved away from the sealing mechanism for enabling the heat insulative block of the press bar to be pressed against the projecting block of the heat insulative base of the sealing mechanism. In an alternate form of the present invention, the safety means comprises a shaft mounted in a hole inside the casing, a stop rod turned about the shaft, and a knob fixedly connected to the stop rod and extended out of a notch on the casing and operated by hand to turn the stop rod about the shaft between a first position where the sealing mechanism is not allowed to be triggered, and a second position where the sealing mechanism is allowed to be triggered. The safety means can be a safety switch, a press-button switch, or an electric connector, or a combination of them. When a press-button switch is used, a protective shielding means is provided for protection. The electric circuit is closed or, opened by operating the safety means of the safety switch, press-button switch or electric connector. In still another alternate form of the present invention, the sealing mechanism is installed in the free end of the press bar.